Tetra

Tetra is our next-generation analog poly synth. Tetra takes the
award-winning sound and features of Mopho, multiplies them by four,
and packs them in a box less than half an inch larger!

Tetra has multiple personalities. It is a
four-voice, analog poly synth, a sort of "mini Prophet." It's a
four-part, multitimbral synth with separate outputs, essentially
four Mophos in one very compact box. And it's a voice
expander for other Tetras or the Prophet '08.

Outside the Box
Physically, Tetra is similar to Mopho, with four assignable
parameter controls per program and a row of controls dedicated to
the most commonly used performance parameters. All of the
parameters can be accessed from the front panel and Tetra is fully
programmable. A free, downloadable editor is available for Mac OS
and Windows to facilitate more comprehensive tweaking.

Most of the rotary controls are detented
encoders, but Cutoff and Resonance are potentiometers, allowing
full sweeps with a single turn. The Push It button is a manual
trigger to play notes and latch sequences on without the need for a
MIDI controller.

Audio is output in mono, stereo, or per
voice, via the four audio output jacks. There is also a headphone
out. MIDI communication is by standard MIDI in and out jacks or
USB. Poly Chain Out is a special, dedicated MIDI output to chain
multiple instruments for increased polyphony.

Under the Hood
The voice architecture is based on the Prophet '08, but with the
addition of a sub-octave generator for each oscillator and a fully
programmable feedback loop for each voice. That breaks down to two
DCOs, a resonant low-pass filter, three DADSR envelope generators,
four LFOS, deep modulation routing, an arpeggiator, and a 16 x 4
analog-style step sequencer per voice. Feedback is capable
of producing effects ranging from mild distortion to fairly extreme
harmonic instability. (That's a good thing.) The possibilities are
nearly endless. And the audio signal path is 100% analog.

Tetra a la Mode
In Program Mode, Tetra is a four-voice, polyphonic synthesizer
with four banks of 128 programs. As with the Prophet '08, each
program contains two layers-each layer is essentially a separate
patch-that can be used to create keyboard splits or stacked sounds.
Banks 1 and 2 are the Prophet '08 factory programs; banks 3 and 4
are a combination of Mopho and new programs.

In Combo Mode, a different program can be
assigned to each of the four voices. Combos can be used for mammoth
unison patches or for triggering up to four different 16 x 4
sequences-each with its own program-simultaneously. Combos can also
be used to create "modular-style" polyphonic patches, where each
voice plays a different program, with a slight variation on the
same sound or even a drastically different sound.

In Multi Mode, Tetra becomes a multitimbral
sound module capable of playing four monophonic parts on four MIDI
channels, with separate outputs for each voice. Coupled with a MIDI
sequencer and DAW, Tetra can play complex arrangements or analog
drum parts with each part individually processed and recorded to
its own track.

This One Goes to 12...and
16
Up to four Tetras can be poly chained for eight, twelve, or
sixteen voices total. When used with a Prophet '08, up to two
Tetras can be poly chained for a maximum of sixteen voices. In
addition, the Prophet's front panel controls map directly to almost
all of Tetra's parameters, so the Prophet acts as a programmer and
control surface. And a Mopho can be connected to Tetra's Poly Chain
Out for five-voice operation.